diff --git a/README.md b/README.md
index 010653e1..9f149463 100644
--- a/README.md
+++ b/README.md
@@ -498,7 +498,7 @@ model=dm9051|w5500,cs=<gpio>,speed=<clk_in_Hz>,intr=<gpio>[,rst=<gpio>]
 ### Battery / ADC
 The NVS parameter "bat_config" sets the ADC1 channel used to measure battery/DC voltage. The "atten" value attenuates the input voltage to the ADC input (the read value maintains a 0-1V rage) where: 0=no attenuation(0..800mV), 1=2.5dB attenuation(0..1.1V), 2=6dB attenuation(0..1.35V), 3=11dB attenuation(0..2.6V). Scale is a float ratio applied to every sample of the 12 bits ADC. A measure is taken every 10s and an average is made every 5 minutes (not a sliding window). Syntax is
 ```
-channel=0..7,scale=<scale>,cells=<2|3>[,atten=<0|1|2|3>]
+channel=0..7,scale=<scale>,cells=<1..3>[,atten=<0|1|2|3>]
 ```
 NB: Set parameter to empty to disable battery reading. For named configurations (SqueezeAMP, Muse ...), this is ignored (except for SqueezeAMP where number of cells is required)